lighte



UNITED STATES PATENT OFFICE.

FERDINAND C. LIGHTE. OF NEWv YORK, N. Y.

PIANOFORTE.

Specification of Letters Patent No. 25,426, dated September 13, 1859.

To all whom 'it may concern:

Be it known that I, FERDINAND C. Lier-rrr, of the city, county, and State of New York, have invented certain new and useful Improvements in Pianofortes; and I do hereby declare that the following is a full, clear, and exact description of the same, reference being had to the accompanying drawings, forming part of this specification, in which- Figure l, is a plan view of the interior of a square pianoforte with my improvement, representing it with a portion of the plate broken away to expose my invention to view. Fig. 2, is a longitudinal vertical section of the same. Fig. 3, is a transverse vertical section of the same.

Similar letters of reference indicate corresponding parts in the several figures.

My invention consists firstly in a plate of glass or other material capable of vibrating freely when struck by the vibrations of the air, arranged below or behind the soundboard of a pianoforte for the purpose of receiving the vibrations of the air on the under side or back of the sound-board and reverberating them through suitable openings provided in the sound-board and so causing the said vibrations to swell the tone of the instrument instead of being all absorbed in the bottom and blocking of the case as in most of the pianofortes in use.

My invention consists secondly in insulating the iron frame or string plate from the wrest plank and wooden blocks upon which it is supported, by applying collars, or washers of india rubber. gutta percha leather, or other suitable moderately yielding material around the screws by which the said frame or plate is bolted to the wrest plank and wooden blocking of the case, so that the said frame or plate shall rest upon the wood work only at a few points, and not over the whole surface thereof and thereby, while a rm bed is provided for the said plate or frame it is prevented interfering with the vibration of the wood work and producing the shortness of tone so common to pianofortes with the full iron frame.

To enable others skilled in the art to make and use my invention I will proceed to describe its construction and operation.

A, is the case of the instrument; B, the wrest plank; F, the wooden blocking; C, the sound-board and D, the iron frame or string plate all of the usual construction and occupying the usual positions, except that the iron frame does not bed all over the wrest plank and wooden blocking as will be presently explained, and that the soundboard has a number of openings a, a, in the part toward the right hand end of the instrument, under which the striking action does not extend and under which is situated the plate of glass or other material G, which constitutes the first mentioned feature of my invention, and which I term the crystal reverberator.

The crystal reverberator Gr, is supported all around its margin in a bed of cloth or other soft material on a suitable arrangement of wooden blocking F, and H. It is arranged a little way below the sound-board and parallel therewith, and occupies asmuch of the space below the sound-board as is consistent with allowing proper room for the striking action as is illustrated in Figs. l and 2, where the letters b, b, indicate the space occupied by the striking action, and c, c, the space occupied by the crystal reverberator. In pianofortes of some other forms as grands or uprights it may extend under or behind a greater portion of thc sound-board than in those of square form. The openings a, a, in the sound-board, it will be observed are over the crystal reverberator and are for the purpose of letting out the sound produced by the vibrations of the air on the under side or back of the sound-board and reverberated by the reverberator. The plate or frame D, has openings CZ, (l, over the openings a., a, of the sound-board, but such openings have generally been made in the said plate or frame in the pianofortes heretofore constructed.

e, c, are the screws by which the plate or frame D, is bolted to the wrest plank and the wooden blocking E, of the instrument, and f, f, are what I term the insulators, of india-rubber, gutta percha, or other material which insulate the plate or frame from the wrest plank and blocking, said insulators being applied in the form of rings or washers to surround the screws c, c, and so support the plate around and close to the yery points where it is secured and leave it free of the wood work in all other parts. These insulators while they combine to constitute a firm bed for the plate and stringed portion of the instrument permit the free Vithe iron frame or plate G, and the wrest bration of all the wood work of the piano plank and wooden blocking of the instruwhich is necessary to its perfection. ment, in such manner that the said frame or What I claim as my invention and desire plate will bear upon the plank and block- 1e 5 to secure by Letters Patent is: ing only at a few points substantially as and l. The crystal reverberator G, of glass for the purpose herein described. or other material applied below or at the back of the sound-board in combination with FEED' C LIGHTE openings a, therein substantially as and lVitnesses: 10 for the purpose herein described. O. D. MUMO,

2. The insulators f, f, applied betweenj GEO.H.GE1B. 

